Date   
Re: AGC circuit to try?

K9HZ <bill@...>
 

That BF2040 is a nice part and i see a few designs with it in my future!  The only down side for the uBITx would be its maximum operating voltage (8 volts).  That can be engineered around obviously but there is a cost for that. 


Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton - J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com


email:  bill@...

 


On Apr 11, 2018, at 2:27 PM, Sandy T <windy10605@...> wrote:

Since dual gate BF998 units are apparently older and either not stocked or obsolete, I would assume the BF2040 is acceptable to try (and inexpensive).

73 Kees K5BCQ 

Re: Ian Lee KD8CEC integration of SDR demo #ubitx

Lawrence Macionski <am_fm_radio@...>
 

I am so glad you're developing this with Simon Brown's SDR-CONSOLE...

Simon started HRD with an FT817, PSK31 and Windows..15+ years ago, as HAM RADIO DELUXE while he was in Switzerland. HRD evolved into bigger and better till, he off loaded it off to continue his pursuits , HRD is now commercial, is still evolving  which requires a subscription.  

Of trying the various SDR programs, SDR# HDSDR etc... I find I like  Simon Brown's  SDR-CONSOLE best. It is intuitive when first using it.  Simon is working on making it so you can assign an IP address and access it via internet remotely in Version 3.

Kudo's to KD8CEC and all the other developers of the uBITX ( Hint- hat's off to you Jim). This is the true tradition of Amateur Radio. Experimentation, building, sharing, both good and bad. Get to togethers and 807's too..

Not every ham in the world can afford a $3000 radio... The most fun I've had with ham radio in my 52 years has been with the less that $$$$ big buck radio, antenna, power levels, and so on...

Larry W8LM

Re: AGC circuit to try?

Tim Gorman
 

Thank you!

I'll have to go through my ham radio magazines to see if I have this
one or if it was part of the boxes I donated to the library.

tim ab0wr

On Wed, 11 Apr 2018 22:57:32 -0500
"M Garza" <mgarza896@...> wrote:

Tim,
I have attached the page that I think you want....
I found it here:
http://hobbydocbox.com/Radio/70955037-Ssb-transceiver-sol-idmstate-80-me-er-this-month-maqaziqe-focus-on-communications-technology-i-march-1973.html#show_full_text

Hope this helps.

Marco - KG5PRT



On Wed, Apr 11, 2018 at 7:33 PM, Tim Gorman <tgorman2@...> wrote:

Any chance you could take a picture of the agc part of that article
and post it?

I gave away both my copies of that book to the local library when I
thought I wouldn't need them any longer!

tim ab0wr

On Wed, 11 Apr 2018 21:38:49 +0200
"Lawrence Galea" <9h1avlaw@...> wrote:

Also used by DL6WD Rudolf Fischer.
See ARRL Single Sideband for the Radio Amateur 1970 p193 et seq.
"An Engineer's Ham-Band Receiver"
Used in the RF amplifier with 0-60dB manual RF gain control
Regards
Lawrence

On Wed, Apr 11, 2018 at 11:45 AM, Dexter N Muir <dexy@...>
wrote:

Bill N2CQR ('Soldersmoke') has been using 2 FETs in
'series'/cascode as dual-gates. Jxxx numbers. Bog-standard,
readily available. AFAIK good NF, gain-bandwidth etc...

73
Dex, ZL2DEX






Re: Baofeng Microphones

 

My solution for Baofeng Mic.

Panel mount mono jacks, one 3.5 and one 2.5, from Radio Shack in store stock (could probably order online), if you turn these back to back, and butt them against each other, with the ears turned out, it is a perfect fit for spacing.  I had posted a picture before, I will look to see if I can find it again.  

I then use only the PTT, and the Mic element in the enclosure, enlarge the hole in front of the element, remove the speaker, and make sure the only two circuits are PTT and MIC, I removed SMD components and unnecessary trace runs by exacto knife cuts.

Works fine for me.

Craig Thibodeaux
KM4YEC


On Apr 12, 2018, at 9:30 AM, David Wilcox via Groups.Io <Djwilcox01@...> wrote:

I like your idea of an adaptor board instead of cutting off the connector. Has anyone made a small board with the double jacks on one end and a single plug on the other?

Another note:  my Baofeng speaker mike was of such poor quality that I bought an almost identical from Btech, QHM22, a much better product for $23.00 USD.  The speaker is top notch and reports of my voice quality are very good now.  So the Btech mike might be a better choice for the Bitx rigs too.

Dave K8WPE

On Apr 12, 2018, at 7:02 AM, Mvs Sarma via Groups.Io <mvs_sarma@...> wrote:

Now a days it is difficult to gety a 2.5 and 3.5 combined plug.
As such  i humbly feelt hat instead of chopping off,  better we have a jack and plug (extension card assembly) and adopt it to original baofeng type (ebay) mic)
 regards
sarma
vu3zmv

Re: YW brand 2822 #ubitx

Arvo W0VRA
 

On Thu, Apr 12, 2018 at 06:55 am, <davesters@...> wrote:
I was going to modify the circuit board if it had a wx chip. But would prefer not to if it isn't needed.
The socket and the non-WX chip indicate that this unit has the corrective action implementation, so the modification is not needed.

Lots of other much more interesting mods are available!  See http://ubitx.net/

Re: AGC circuit to try?

Tim Gorman
 

this link just won't work for me. Not even when I am logged in as an
arrl member.

tim ab0wr

On Wed, 11 Apr 2018 23:18:28 -0500
"M Garza" <mgarza896@...> wrote:

Tim,
Here is the article directly from the ARRL QST Archive:
http://p1k.arrl.org/pubs_archive/62188

Marco - KG5PRT

On Wed, Apr 11, 2018 at 10:57 PM, M Garza <mgarza896@...> wrote:

Tim,
I have attached the page that I think you want....
I found it here:
http://hobbydocbox.com/Radio/70955037-Ssb-transceiver-sol-
idmstate-80-me-er-this-month-maqaziqe-focus-on-
communications-technology-i-march-1973.html#show_full_text

Hope this helps.

Marco - KG5PRT



On Wed, Apr 11, 2018 at 7:33 PM, Tim Gorman <tgorman2@...>
wrote:
Any chance you could take a picture of the agc part of that
article and post it?

I gave away both my copies of that book to the local library when I
thought I wouldn't need them any longer!

tim ab0wr

On Wed, 11 Apr 2018 21:38:49 +0200
"Lawrence Galea" <9h1avlaw@...> wrote:

Also used by DL6WD Rudolf Fischer.
See ARRL Single Sideband for the Radio Amateur 1970 p193 et seq.
"An Engineer's Ham-Band Receiver"
Used in the RF amplifier with 0-60dB manual RF gain control
Regards
Lawrence

On Wed, Apr 11, 2018 at 11:45 AM, Dexter N Muir <dexy@...>
wrote:

Bill N2CQR ('Soldersmoke') has been using 2 FETs in
'series'/cascode as dual-gates. Jxxx numbers. Bog-standard,
readily available. AFAIK good NF, gain-bandwidth etc...

73
Dex, ZL2DEX







Re: AGC circuit to try?

Tim Gorman
 

Might be something to try in the future.

Thanks,

tim ab0wr

On Thu, 12 Apr 2018 06:09:07 -0700
"ajparent1" <kb1gmx@...> wrote:

Tim,

The image with three fets is a good circuit and works abut has one
significant problem The input and output impedances are high at max
attenuation.  This would terminate the DBM and the low pass filter
very badly.   

It does work at audio.  BEst place for it would be between the
product detector and RX preamp as it can also be the RX pop
suppression and TX audio to RX audio path suppression.

Again for RF you would have to switch it out of the transmit path or
insure the TX attenuation was "minimum".... Unless you want to
implement Transmit AGC as well.

Allison

Re: AGC circuit to try?

Tim Gorman
 

Marco,

Thanks! I'll take a look at it!

tim ab0wr

On Wed, 11 Apr 2018 23:18:28 -0500
"M Garza" <mgarza896@...> wrote:

http://p1k.arrl.org/pubs_archive/62188

Re: AGC circuit to try?

K9HZ <bill@...>
 

Worked for me.  I can send it to you via email tonight. 


Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton - J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com


email:  bill@...

 


On Apr 12, 2018, at 11:04 AM, Tim Gorman <tgorman2@...> wrote:

this link just won't work for me. Not even when I am logged in as an
arrl member.

tim ab0wr

On Wed, 11 Apr 2018 23:18:28 -0500
"M Garza" <mgarza896@...> wrote:

Tim,
Here is the article directly from the ARRL QST Archive:
http://p1k.arrl.org/pubs_archive/62188

Marco - KG5PRT

On Wed, Apr 11, 2018 at 10:57 PM, M Garza <mgarza896@...> wrote:

Tim,
I have attached the page that I think you want....
I found it here:
http://hobbydocbox.com/Radio/70955037-Ssb-transceiver-sol-
idmstate-80-me-er-this-month-maqaziqe-focus-on-
communications-technology-i-march-1973.html#show_full_text

Hope this helps.

Marco - KG5PRT



On Wed, Apr 11, 2018 at 7:33 PM, Tim Gorman <tgorman2@...>
wrote:
Any chance you could take a picture of the agc part of that
article and post it?

I gave away both my copies of that book to the local library when I
thought I wouldn't need them any longer!

tim ab0wr

On Wed, 11 Apr 2018 21:38:49 +0200
"Lawrence Galea" <9h1avlaw@...> wrote:

Also used by DL6WD Rudolf Fischer.
See ARRL Single Sideband for the Radio Amateur 1970 p193 et seq.
"An Engineer's Ham-Band Receiver"
Used in the RF amplifier with 0-60dB manual RF gain control
Regards
Lawrence

On Wed, Apr 11, 2018 at 11:45 AM, Dexter N Muir <dexy@...>
wrote:

Bill N2CQR ('Soldersmoke') has been using 2 FETs in
'series'/cascode as dual-gates. Jxxx numbers. Bog-standard,
readily available. AFAIK good NF, gain-bandwidth etc...

73
Dex, ZL2DEX
















Re: AGC circuit to try?

Kees T
 

Going back to an audio AGC (I know it has drawbacks but that is what the "original" uBITX had), here are some quick bench meter data from a H11F3M Optocoupler:

Output resistance       Input voltage     Input current
Rd-s equal to Rs-d       DC                   
1K................................12.0V.................20mA
2K.................................6.3V..................8.8mA
5K.................................3.0V..................3.1mA
10K...............................1.24V................0.1mA 
50K...............................1.1V..................0.4mA

73 Kees K5BCQ

TDA2822 fried

Xcott Craver
 

My TDA2822 just went up in an impressive display of smoke and sparks---glad I had the top of the case off so I could see it.  This board was shipped March 9th.  It's a WX chip soldered directly to the mainboard.   This happened in the 2nd test run, after about 5-10 minutes of use.  I think it was on for about 15 minutes grand total since I assembled it.

Now it's time for me to arrange a fix---I guess I'll search through the archive to see what approach is best.  For what it's worth, we bought an early uBITX back in December and used that one a while with digital modes without any issues.   I'm guessing that this is consistent with the theory that some WX chips conk out early.

Best, Xcott K2CAJ

Re: Audio squealing

L Sechrist
 

Arv, 
I have limited test equipment, just a VOM. I tried your suggestions and nothing worked. However I ordered new LM386 chip and installed one of those and that got rid of the squeal. The audio output is very low but useable. Thanks for your help.

Re: TDA2822 fried

Arvo W0VRA
 

On Thu, Apr 12, 2018 at 10:28 am, Xcott Craver wrote:
Now it's time for me to arrange a fix---I guess I'll search through the archive to see what approach is best.
Bummer!

If none of the surrounding components went with it (hope that's not scary), then get another from a reputable source and swap it out.

Some are adding sockets, but you'll likely never need to replace it again.

Others add supply voltage regulation schemes, but the evidence for the necessity of that for reputable parts is scant at best.

Good luck!

Re: AGC circuit to try?

ajparent1/KB1GMX
 

https://www.digikey.com/product-detail/en/nxp-usa-inc/BF992215/568-1971-1-ND/807567

in stock as of this posting.

BF992, 58 cents  The BF99x series had parts with mirror pinouts, handy for things like balanced mixers.
its a 20V device good to 200mhz and other than SOT143 a drop in for many of the older dual gate parts.

Allison

Re: TDA2822 fried

Joe Puma
 

I just received some 8pin dip sockets along with the NTE7155 audio amplifier that Mike Olsen here in the group suggested. 

image1.jpeg



On Apr 12, 2018, at 1:28 PM, Xcott Craver <xcottcraver@...> wrote:

My TDA2822 just went up in an impressive display of smoke and sparks---glad I had the top of the case off so I could see it.  This board was shipped March 9th.  It's a WX chip soldered directly to the mainboard.   This happened in the 2nd test run, after about 5-10 minutes of use.  I think it was on for about 15 minutes grand total since I assembled it.

Now it's time for me to arrange a fix---I guess I'll search through the archive to see what approach is best.  For what it's worth, we bought an early uBITX back in December and used that one a while with digital modes without any issues.   I'm guessing that this is consistent with the theory that some WX chips conk out early.

Best, Xcott K2CAJ

Re: Ian Lee KD8CEC integration of SDR demo #ubitx

Joe Puma
 

SDR Console is my go to SDR program. The External Radio is feature is great but Simon is still working out bugs for official release. It defentily requires a beefy computer but the experience you get with the program is amazing. HDSDR is second best for Pan-adapter use IMO. 


Joe
KD2NFC



On Apr 12, 2018, at 11:51 AM, Lawrence Macionski via Groups.Io <am_fm_radio@...> wrote:

I am so glad you're developing this with Simon Brown's SDR-CONSOLE...

Simon started HRD with an FT817, PSK31 and Windows..15+ years ago, as HAM RADIO DELUXE while he was in Switzerland. HRD evolved into bigger and better till, he off loaded it off to continue his pursuits , HRD is now commercial, is still evolving  which requires a subscription.  

Of trying the various SDR programs, SDR# HDSDR etc... I find I like  Simon Brown's  SDR-CONSOLE best. It is intuitive when first using it.  Simon is working on making it so you can assign an IP address and access it via internet remotely in Version 3.

Kudo's to KD8CEC and all the other developers of the uBITX ( Hint- hat's off to you Jim). This is the true tradition of Amateur Radio. Experimentation, building, sharing, both good and bad. Get to togethers and 807's too..

Not every ham in the world can afford a $3000 radio... The most fun I've had with ham radio in my 52 years has been with the less that $$$$ big buck radio, antenna, power levels, and so on...

Larry W8LM

Re: Ian Lee KD8CEC integration of SDR demo #ubitx

Rob Snow
 

Oh, my.  This is pure awesomeness.  What hardware mods are required?

-Rob

Re: TDA2822 fried

Daniel Conklin
 

While I may be a pyrotechnic junkie and would have liked to see that, I soldered a 7806 regulator in the power line to the chip before I ever put power to the board.  I've been abusing it for a couple of weeks now with no problems. Here's the link:  https://groups.io/g/BITX20/message/44455
Dan W2DLC

Re: TDA2822 fried

K4LXY
 

I'm using the NJM2073D.  It's a  plug-and-play replacement and seems to be doing fine.
Howard

Re: uBITX shipping time

 

Looks like shipping is catching up. My ubitx ordered Mar 1 shipped today Apr 12
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